PY Numbers for 2017

Originally posted by jeffers We are getting pressure at Hunts to tweak the D-Zero PY, people feel it is favoured. funnily enough one of the biggest vices is from some who sails a class that recently had a big evolution in terms of hull weight..... go figure.

If the number is genuinely wrong at Hunts, it will be genuinely wrong at many dozens of comparable clubs.
Personally, I've only sailed against one Dzero, it did very well, but the helm was clearly very good. Seemed to tack in no time losing no speed. But the helm has a long history at that club and probably knew what the wind was going to do way better than me. Not sure the upwind boat speed in light air is special when the wind is steady, but gained on every puff. Possibly 'responsive' and 'quick' rather than 'fast'? Just my impression.
I was in the 400 so obviously giving him a lot of minutes anyway, but I was making a lot of mistakes starting in current, being either late or early and going back, so I saw a lot of the other boats!

Originally posted by Sam.Spoons .... I said in t'other thread that it should be easy enough to work out how much advantage dropping 15kg of the hull weight or adding an extra metre of sail might bring and PNs adjusted accordingly. I'm not sure what happened to the 'nova when they reduced the weight, or the Merlin when they adopted a 25% larger kite but shouldn't any fundamental change to a boats specification attract a new EN based on such a calculation?

You can work these things out, and very often the difference it's going to make is remarkably small, for a boat sailing around a course on its own.
It makes a much bigger difference when sailing in a fleet. Where the tiniest edge means a place at a mark etc.
And of course all the pre-existing Novas stayed the same weight etc. So unless you want a vast database of age related PY's, there is a limit to the benefit in complicating things. Particularly in the face of people losing confidence in the basics.

Originally posted by RS400atC Originally posted by jeffers We are getting pressure at Hunts to tweak the D-Zero PY, people feel it is favoured. funnily enough one of the biggest vices is from some who sails a class that recently had a big evolution in terms of hull weight..... go figure. If the number is genuinely wrong at Hunts, it will be genuinely wrong at many dozens of comparable clubs. Personally, I've only sailed against one Dzero, it did very well, but the helm was clearly very good. Seemed to tack in no time losing no speed. But the helm has a long history at that club and probably knew what the wind was going to do way better than me. Not sure the upwind boat speed in light air is special when the wind is steady, but gained on every puff. Possibly 'responsive' and 'quick' rather than 'fast'? Just my impression. I was in the 400 so obviously giving him a lot of minutes anyway, but I was making a lot of mistakes starting in current, being either late or early and going back, so I saw a lot of the other boats!

http://www.rya.org.uk/SiteCollectionDocuments/technical/Web%20Documents/PY%20Documentation/PN%20List%202017%20(Web%20Version).pdf

Originally posted by Rupert Plenty of basis in fact, but still 1 or 2 point movements which don't tie in with individual perception. Usually the bigger movements fit in better with what people see. Phantom back up 5 points, laser and radial inexplicably slower again. Solo and Streaker to change slightly randomly, British Moth once more 40 points out for anyone racing on open water. OK still wrong, but no idea why?

Damn I was close. 4 points for the Phantom, Streaker and Solo move randomly, BM down yet again, OK moves a token point. And yes, Laser and Radial slower once more.